Block client writes if not possible perform sync replication

[Anton]

Hello,

Is it possible to temporarily block NFS client writes if DRBD can’t perform sync replication for NFS server to secondary node ?, for instance, if primary node is rebooting ?

[kermat]

If the Primary node is rebooting, how is DRBD accepting writes? If the DRBD Primary is rebooting, DRBD should be demoted to a Secondary first, and therefore not accept any writes.